Convert from Polar to Rectangular Coordinates on the TI-83 Plus

You can use the TI-83 Plus graphing calculator to convert from polar to rectangular coordinates. You’re used to seeing points in the xy-plane displayed in the (x, y) rectangular form.

Press [2nd][APPS][2] to select

from the Angle menu. (On the TI-83, press [2nd][MATRX][7].)

Enter

and press [ENTER] to display the x-coordinate of the point (x, y).

To do so, enter r, press [.], enter

press [ ) ], and then press [ENTER]. The value of x-coordinate appears on the right of the screen. If your calculator is in Degree mode,

should be entered in degrees; if the calculator is in Radian mode,

should be entered in radian measure.

If the calculator is in Degree mode, but you want to enter an angle in radian measure, enter the radian measure of the angle (surrounded by parentheses, if necessary) and then press [2nd][APPS][3] to indicate that it’s in radian measure. (On the TI-83, press [2nd][MATRX][3].) If you want to indicate that an angle is in degree measure when the calculator is in Radian mode, press [2nd][APPS][1]. (On the TI-83, press [2nd][MATRX][1].)